27166542827821 has 2 divisors, whose sum is σ = 27166542827822. Its totient is φ = 27166542827820.

The previous prime is 27166542827807. The next prime is 27166542827861. The reversal of 27166542827821 is 12872824566172.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19037121554025 + 8129421273796 = 4363155^2 + 2851214^2 .

It is a cyclic number.

It is not a de Polignac number, because 27166542827821 - 2⁹ = 27166542827309 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 27166542827821.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (27166542827861) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13583271413910 + 13583271413911.

It is an arithmetic number, because the mean of its divisors is an integer number (13583271413911).

Almost surely, 2^{27166542827821} is an apocalyptic number.

It is an amenable number.

27166542827821 is a deficient number, since it is larger than the sum of its proper divisors (1).

27166542827821 is an equidigital number, since it uses as much as digits as its factorization.

27166542827821 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 36126720, while the sum is 61.

The spelling of 27166542827821 in words is "twenty-seven trillion, one hundred sixty-six billion, five hundred forty-two million, eight hundred twenty-seven thousand, eight hundred twenty-one".